RESUMO
BACKGROUND: We investigated the associations between second trimester amniotic fluid (AF) levels of human adiponectin and placental growth factor (PLGF) in small for gestational age (SGA), large for gestational age (LGA) and appropriate for gestational age (AGA) fetuses. MATERIALS AND METHODS: Adiponectin and PLGF levels were determined by enzyme immunoassay in AF of 21 SGA, 13 LGA and 44 AGA fetuses between 15-22 weeks of gestation, derived from pregnant women who underwent amniocentesis. RESULTS: Adiponectin and PLGF levels were detectable in AF. Median (25th-75th percentile) adiponectin levels were 16.1 (10.9-32.3) ng/ml in SGA, 19.5 (15.1-30.9) ng/ml in AGA, and 18.2 (14.7-30.8) ng/ml in LGA fetuses. Median (25th-75th percentile) PLGF levels were 24.2 (19.9-34.9) pg/nl in SGA, 26.4 (20.9-33.8) pg/ml in AGA and 33.5 (21.8-40.4) pg/ml in LGA fetuses. The differences were not statistically significant. Nevertheless, indication of differentiation of levels existed when SGA and LGA fetuses in the extremes of distribution were considered. Specifically, very severely SGA fetuses (≤2.5th percentile) tended to have high levels of adiponectin and reduced levels of PLGF in AF. CONCLUSION: This is the first study presenting adiponectin and PLGF concentrations in early second trimester amniotic fluid in AGA, SGA and LGA fetuses. The altered concentrations of adiponectin and PLGF in very severely SGA fetuses possibly result from the growth-promoting effect of these factors through the metabolic route and the vascular integrity of the placenta, respectively.
